A pen-shaped position indicator generally includes a resonant coil for detecting a position. The resonant coil is arranged in the vicinity of the tip of the pen shape (e.g., see Japanese Unexamined Patent Application Publication No. 2001-319831). However, a magnetic core of the position indicator, around which the resonant coil is wound, may be damaged by impact when the position indicator is dropped or falls.
Because the magnetic core utilized in prior position indicator(s) is formed of soft magnetic molded metal product, it is usually fragile against impact. In the prior position indicators, a buffer material is typically provided around the resonant coil and core. The buffer material results in an increase in the number of components and an increase in a diameter of the magnetic core of the position indicator.
An increased number of position indicators have recently been utilized in compact mobile information terminals such as PDAs (Personal Digital Assistant). The position indicator of the compact mobile information terminal preferably has a thin, compact diameter. For example, in certain PDA's, the position indicator is required to be sufficiently thin so as to be housed in the PDA. It is possible to form an indicator having a small diameter with materials used in the prior devices; however, the strength of the material of the indicator decreases as the thickness thereof decreases. Thus, the position indicator may not be strong enough to withstand the impact when it is dropped or when the position indicator is forced against a surface by a user's hand. As a result, the position indicator may bend or the magnetic core thereof may be broken.
Accordingly, there is a need for a compact position indicator having an impact resistant magnetic core.